The present invention relates to a composite magnetic and optical head capable of simultaneously reading magnetic and optical patterns recorded on a record medium, such as paper money.
The inventor hereof proposed such a composite head which can simultaneously detect a magnetic pattern and an optical pattern recorded on the same position on a record medium, such as paper money (Japanese Utility Model Disclosure No. 61-125763). In this composite head, a light transmitting member (optical member) formed of a light transmitting nonmagnetic material is attached to a magnetic detector gap (distal gap) of a magnetic sensor, which is formed by winding coils on magnetic cores. An optical fiber bundle, used to read optical data, is connected to the optical member, and the magnetic sensor is covered with a bisected holder for holding and fixing the same.
Magnetic and optical patterns are simultaneously put on the surface of paper money or other record medium by using printing ink mixed with magnetic powder. As the record medium is moved in intimate contact with the gap of the composite magnetic and optical head, the head reads the magnetic pattern by detecting the time-based change of the induced current or impedance of the coils on the magnetic cores. At the same time, a light from a light emitting element is guided to a transparent optical member through an optical fiber bundle for incidence, and is reflected by the record medium. The reflected light is guided to a light sensing element through an optical fiber bundle for reflection. Thus, the optical pattern is read.
The record medium is identified by means of a multihead which is composed of a plurality of composite magnetic and optical heads arranged in a row. In order to improve the identification accuracy of the multihead, the individual composite heads must be minimized in size, and the gaps between the adjacent heads must be narrowed.
In the prior art composite magnetic and optical head, however, a number of optical fiber bundles, magnetic terminals, etc., are arranged mixedly and complicatedly within a narrow space in the holder. Thus, the assembling work requires much time and labor. At the time of a soldering operation, moreover, a soldering iron may touch the optical fibers or the like, thereby damaging or cutting off the same. Conventionally, therefore, it is hard to miniaturize the composite head.